crypto/evp/encode.c

   1 /* crypto/evp/encode.c */
   2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
   3  * All rights reserved.
   4  *
   5  * This package is an SSL implementation written
   6  * by Eric Young (eay@cryptsoft.com).
   7  * The implementation was written so as to conform with Netscapes SSL.
   8  *
   9  * This library is free for commercial and non-commercial use as long as
  10  * the following conditions are aheared to.  The following conditions
  11  * apply to all code found in this distribution, be it the RC4, RSA,
  12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
  13  * included with this distribution is covered by the same copyright terms
  14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
  15  *
  16  * Copyright remains Eric Young's, and as such any Copyright notices in
  17  * the code are not to be removed.
  18  * If this package is used in a product, Eric Young should be given attribution
  19  * as the author of the parts of the library used.
  20  * This can be in the form of a textual message at program startup or
  21  * in documentation (online or textual) provided with the package.
  22  *
  23  * Redistribution and use in source and binary forms, with or without
  24  * modification, are permitted provided that the following conditions
  25  * are met:
  26  * 1. Redistributions of source code must retain the copyright
  27  *    notice, this list of conditions and the following disclaimer.
  28  * 2. Redistributions in binary form must reproduce the above copyright
  29  *    notice, this list of conditions and the following disclaimer in the
  30  *    documentation and/or other materials provided with the distribution.
  31  * 3. All advertising materials mentioning features or use of this software
  32  *    must display the following acknowledgement:
  33  *    "This product includes cryptographic software written by
  34  *     Eric Young (eay@cryptsoft.com)"
  35  *    The word 'cryptographic' can be left out if the rouines from the library
  36  *    being used are not cryptographic related :-).
  37  * 4. If you include any Windows specific code (or a derivative thereof) from
  38  *    the apps directory (application code) you must include an acknowledgement:
  39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
  40  *
  41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
  42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  51  * SUCH DAMAGE.
  52  *
  53  * The licence and distribution terms for any publically available version or
  54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
  55  * copied and put under another distribution licence
  56  * [including the GNU Public Licence.]
  57  */
  58
  59 #include <stdio.h>
  60 #include "cryptlib.h"
  61 #include <openssl/evp.h>
  62
  63 #define conv_bin2ascii(a)       (data_bin2ascii[(a)&0x3f])
  64 #define conv_ascii2bin(a)       (data_ascii2bin[(a)&0x7f])
  65
  66 /* 64 char lines
  67  * pad input with 0
  68  * left over chars are set to =
  69  * 1 byte  => xx==
  70  * 2 bytes => xxx=
  71  * 3 bytes => xxxx
  72  */
  73 #define BIN_PER_LINE    (64/4*3)
  74 #define CHUNKS_PER_LINE (64/4)
  75 #define CHAR_PER_LINE   (64+1)
  76
  77 static unsigned char data_bin2ascii[65]="ABCDEFGHIJKLMNOPQRSTUVWXYZ\
  78 abcdefghijklmnopqrstuvwxyz0123456789+/";
  79
  80 /* 0xF0 is a EOLN
  81  * 0xF1 is ignore but next needs to be 0xF0 (for \r\n processing).
  82  * 0xF2 is EOF
  83  * 0xE0 is ignore at start of line.
  84  * 0xFF is error
  85  */
  86
  87 #define B64_EOLN                0xF0
  88 #define B64_CR                  0xF1
  89 #define B64_EOF                 0xF2
  90 #define B64_WS                  0xE0
  91 #define B64_ERROR               0xFF
  92 #define B64_NOT_BASE64(a)       (((a)|0x13) == 0xF3)
  93
  94 static unsigned char data_ascii2bin[128]={
  95         0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
  96         0xFF,0xE0,0xF0,0xFF,0xFF,0xF1,0xFF,0xFF,
  97         0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
  98         0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
  99         0xE0,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,0xFF,
 100         0xFF,0xFF,0xFF,0x3E,0xFF,0xF2,0xFF,0x3F,
 101         0x34,0x35,0x36,0x37,0x38,0x39,0x3A,0x3B,
 102         0x3C,0x3D,0xFF,0xFF,0xFF,0x00,0xFF,0xFF,
 103         0xFF,0x00,0x01,0x02,0x03,0x04,0x05,0x06,
 104         0x07,0x08,0x09,0x0A,0x0B,0x0C,0x0D,0x0E,
 105         0x0F,0x10,0x11,0x12,0x13,0x14,0x15,0x16,
 106         0x17,0x18,0x19,0xFF,0xFF,0xFF,0xFF,0xFF,
 107         0xFF,0x1A,0x1B,0x1C,0x1D,0x1E,0x1F,0x20,
 108         0x21,0x22,0x23,0x24,0x25,0x26,0x27,0x28,
 109         0x29,0x2A,0x2B,0x2C,0x2D,0x2E,0x2F,0x30,
 110         0x31,0x32,0x33,0xFF,0xFF,0xFF,0xFF,0xFF,
 111         };
 112
 113 void EVP_EncodeInit(EVP_ENCODE_CTX *ctx)
 114         {
 115         ctx->length=48;
 116         ctx->num=0;
 117         ctx->line_num=0;
 118         }
 119
 120 void EVP_EncodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl,
 121              unsigned char *in, int inl)
 122         {
 123         int i,j;
 124         unsigned int total=0;
 125
 126         *outl=0;
 127         if (inl == 0) return;
 128         if ((ctx->num+inl) < ctx->length)
 129                 {
 130                 memcpy(&(ctx->enc_data[ctx->num]),in,inl);
 131                 ctx->num+=inl;
 132                 return;
 133                 }
 134         if (ctx->num != 0)
 135                 {
 136                 i=ctx->length-ctx->num;
 137                 memcpy(&(ctx->enc_data[ctx->num]),in,i);
 138                 in+=i;
 139                 inl-=i;
 140                 j=EVP_EncodeBlock(out,ctx->enc_data,ctx->length);
 141                 ctx->num=0;
 142                 out+=j;
 143                 *(out++)='\n';
 144                 *out='\0';
 145                 total=j+1;
 146                 }
 147         while (inl >= ctx->length)
 148                 {
 149                 j=EVP_EncodeBlock(out,in,ctx->length);
 150                 in+=ctx->length;
 151                 inl-=ctx->length;
 152                 out+=j;
 153                 *(out++)='\n';
 154                 *out='\0';
 155                 total+=j+1;
 156                 }
 157         if (inl != 0)
 158                 memcpy(&(ctx->enc_data[0]),in,inl);
 159         ctx->num=inl;
 160         *outl=total;
 161         }
 162
 163 void EVP_EncodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl)
 164         {
 165         unsigned int ret=0;
 166
 167         if (ctx->num != 0)
 168                 {
 169                 ret=EVP_EncodeBlock(out,ctx->enc_data,ctx->num);
 170                 out[ret++]='\n';
 171                 out[ret]='\0';
 172                 ctx->num=0;
 173                 }
 174         *outl=ret;
 175         }
 176
 177 int EVP_EncodeBlock(unsigned char *t, unsigned char *f, int dlen)
 178         {
 179         int i,ret=0;
 180         unsigned long l;
 181
 182         for (i=dlen; i > 0; i-=3)
 183                 {
 184                 if (i >= 3)
 185                         {
 186                         l=      (((unsigned long)f[0])<<16L)|
 187                                 (((unsigned long)f[1])<< 8L)|f[2];
 188                         *(t++)=conv_bin2ascii(l>>18L);
 189                         *(t++)=conv_bin2ascii(l>>12L);
 190                         *(t++)=conv_bin2ascii(l>> 6L);
 191                         *(t++)=conv_bin2ascii(l     );
 192                         }
 193                 else
 194                         {
 195                         l=((unsigned long)f[0])<<16L;
 196                         if (i == 2) l|=((unsigned long)f[1]<<8L);
 197
 198                         *(t++)=conv_bin2ascii(l>>18L);
 199                         *(t++)=conv_bin2ascii(l>>12L);
 200                         *(t++)=(i == 1)?'=':conv_bin2ascii(l>> 6L);
 201                         *(t++)='=';
 202                         }
 203                 ret+=4;
 204                 f+=3;
 205                 }
 206
 207         *t='\0';
 208         return(ret);
 209         }
 210
 211 void EVP_DecodeInit(EVP_ENCODE_CTX *ctx)
 212         {
 213         ctx->length=30;
 214         ctx->num=0;
 215         ctx->line_num=0;
 216         ctx->expect_nl=0;
 217         }
 218
 219 /* -1 for error
 220  *  0 for last line
 221  *  1 for full line
 222  */
 223 int EVP_DecodeUpdate(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl,
 224              unsigned char *in, int inl)
 225         {
 226         int seof= -1,eof=0,rv= -1,ret=0,i,v,tmp,n,ln,tmp2,exp_nl;
 227         unsigned char *d;
 228
 229         n=ctx->num;
 230         d=ctx->enc_data;
 231         ln=ctx->line_num;
 232         exp_nl=ctx->expect_nl;
 233
 234         /* last line of input. */
 235         if ((inl == 0) || ((n == 0) && (conv_ascii2bin(in[0]) == B64_EOF)))
 236                 { rv=0; goto end; }
 237
 238         /* We parse the input data */
 239         for (i=0; i<inl; i++)
 240                 {
 241                 /* If the current line is > 80 characters, scream alot */
 242                 if (ln >= 80) { rv= -1; goto end; }
 243
 244                 /* Get char and put it into the buffer */
 245                 tmp= *(in++);
 246                 v=conv_ascii2bin(tmp);
 247                 /* only save the good data :-) */
 248                 if (!B64_NOT_BASE64(v))
 249                         {
 250                         d[n++]=tmp;
 251                         ln++;
 252                         }
 253                 else if (v == B64_ERROR)
 254                         {
 255                         rv= -1;
 256                         goto end;
 257                         }
 258
 259                 /* have we seen a '=' which is 'definitly' the last
 260                  * input line.  seof will point to the character that
 261                  * holds it. and eof will hold how many characters to
 262                  * chop off. */
 263                 if (tmp == '=')
 264                         {
 265                         if (seof == -1) seof=n;
 266                         eof++;
 267                         }
 268
 269                 /* eoln */
 270                 if (v == B64_EOLN)
 271                         {
 272                         ln=0;
 273                         if (exp_nl)
 274                                 {
 275                                 exp_nl=0;
 276                                 continue;
 277                                 }
 278                         }
 279                 exp_nl=0;
 280
 281                 /* If we are at the end of input and it looks like a
 282                  * line, process it. */
 283                 if (((i+1) == inl) && (((n&3) == 0) || eof))
 284                         v=B64_EOF;
 285
 286                 if ((v == B64_EOF) || (n >= 64))
 287                         {
 288                         /* This is needed to work correctly on 64 byte input
 289                          * lines.  We process the line and then need to
 290                          * accept the '\n' */
 291                         if ((v != B64_EOF) && (n >= 64)) exp_nl=1;
 292                         tmp2=v;
 293                         if (n > 0)
 294                                 {
 295                                 v=EVP_DecodeBlock(out,d,n);
 296                                 if (v < 0) { rv=0; goto end; }
 297                                 n=0;
 298                                 ret+=(v-eof);
 299                                 }
 300                         else
 301                                 {
 302                                 eof=1;
 303                                 v=0;
 304                                 }
 305
 306                         /* This is the case where we have had a short
 307                          * but valid input line */
 308                         if ((v < ctx->length) && eof)
 309                                 {
 310                                 rv=0;
 311                                 goto end;
 312                                 }
 313                         else
 314                                 ctx->length=v;
 315
 316                         if (seof >= 0) { rv=0; goto end; }
 317                         out+=v;
 318                         }
 319                 }
 320         rv=1;
 321 end:
 322         *outl=ret;
 323         ctx->num=n;
 324         ctx->line_num=ln;
 325         ctx->expect_nl=exp_nl;
 326         return(rv);
 327         }
 328
 329 int EVP_DecodeBlock(unsigned char *t, unsigned char *f, int n)
 330         {
 331         int i,ret=0,a,b,c,d;
 332         unsigned long l;
 333
 334         /* trim white space from the start of the line. */
 335         while ((conv_ascii2bin(*f) == B64_WS) && (n > 0))
 336                 {
 337                 f++;
 338                 n--;
 339                 }
 340
 341         /* strip off stuff at the end of the line
 342          * ascii2bin values B64_WS, B64_EOLN, B64_EOLN and B64_EOF */
 343         while ((n > 3) && (B64_NOT_BASE64(conv_ascii2bin(f[n-1]))))
 344                 n--;
 345
 346         if (n%4 != 0) return(-1);
 347
 348         for (i=0; i<n; i+=4)
 349                 {
 350                 a=conv_ascii2bin(*(f++));
 351                 b=conv_ascii2bin(*(f++));
 352                 c=conv_ascii2bin(*(f++));
 353                 d=conv_ascii2bin(*(f++));
 354                 if (    (a & 0x80) || (b & 0x80) ||
 355                         (c & 0x80) || (d & 0x80))
 356                         return(-1);
 357                 l=(     (((unsigned long)a)<<18L)|
 358                         (((unsigned long)b)<<12L)|
 359                         (((unsigned long)c)<< 6L)|
 360                         (((unsigned long)d)     ));
 361                 *(t++)=(unsigned char)(l>>16L)&0xff;
 362                 *(t++)=(unsigned char)(l>> 8L)&0xff;
 363                 *(t++)=(unsigned char)(l     )&0xff;
 364                 ret+=3;
 365                 }
 366         return(ret);
 367         }
 368
 369 int EVP_DecodeFinal(EVP_ENCODE_CTX *ctx, unsigned char *out, int *outl)
 370         {
 371         int i;
 372
 373         *outl=0;
 374         if (ctx->num != 0)
 375                 {
 376                 i=EVP_DecodeBlock(out,ctx->enc_data,ctx->num);
 377                 if (i < 0) return(-1);
 378                 ctx->num=0;
 379                 *outl=i;
 380                 return(1);
 381                 }
 382         else
 383                 return(1);
 384         }
 385
 386 #ifdef undef
 387 int EVP_DecodeValid(unsigned char *buf, int len)
 388         {
 389         int i,num=0,bad=0;
 390
 391         if (len == 0) return(-1);
 392         while (conv_ascii2bin(*buf) == B64_WS)
 393                 {
 394                 buf++;
 395                 len--;
 396                 if (len == 0) return(-1);
 397                 }
 398
 399         for (i=len; i >= 4; i-=4)
 400                 {
 401                 if (    (conv_ascii2bin(buf[0]) >= 0x40) ||
 402                         (conv_ascii2bin(buf[1]) >= 0x40) ||
 403                         (conv_ascii2bin(buf[2]) >= 0x40) ||
 404                         (conv_ascii2bin(buf[3]) >= 0x40))
 405                         return(-1);
 406                 buf+=4;
 407                 num+=1+(buf[2] != '=')+(buf[3] != '=');
 408                 }
 409         if ((i == 1) && (conv_ascii2bin(buf[0]) == B64_EOLN))
 410                 return(num);
 411         if ((i == 2) && (conv_ascii2bin(buf[0]) == B64_EOLN) &&
 412                 (conv_ascii2bin(buf[0]) == B64_EOLN))
 413                 return(num);
 414         return(1);
 415         }
 416 #endif